Fiber optic infrastructure is currently being deployed by the assignee of the present invention with its fiber-optic system program, and is being operatively connected to its customer base. Fiber optic telecommunication infrastructure offers many advantages over the old standard copper wire cabling, not the least of which is vastly increased bandwidth. “Plain old telephone service” (POTS) had operated, and still operates, with copper wiring. POTS is now being made compatible with fiber optic cabling, such as in passive optical networks (PONs).
However, providing POTS service in combination with this new PON fiber optic infrastructure involves certain optically-related and/or other functionality not previously needed in the copper wire cabling world. For example, an optical line terminal (OLT) is needed which may be located in the central office of the relevant telecommunications company or at some other regional location (but not on customer premises). The OLT is communicatively coupled via fiber optic cable to an optical network terminal (ONT) which can be located immediately outside of a customer's premises on an outside wall some four to five feet above ground, or can be located inside a customer's premises such as in a basement.
The ONT includes and is powered by a power supply such as, for example, a power supply similar, or related, to that described in patent application Ser. No. 11/144,566 filed Jun. 3, 2005, and incorporated herein by reference in its entirety. That patent application is entitled “Multi-Component ONT Power Supply” and its assignee is in common with that of the instant application. That patent application claims benefit of provisional application Ser. No. 60/576,675 filed Jun. 3, 2004. That power supply is, in turn, powered by typical electric utility company power which is subject to power failure for any number of reasons including, for example, power company equipment failure, local or national emergencies, natural disasters, terrorist attacks, etc.
During a utility company power failure, battery backup is needed. Traditional POTS telephone service over copper wiring is ordinarily able to continue because of POTS battery back-up infrastructure which is in place at telecommunication company central offices. This battery backup system is designed to maintain POTS telephone service for an entire community. But, that otherwise—available POTS telephone service will not be available to a telephone customer using a PON system, if the ONT cannot communicate with the OLT over the fiber optic cable because the ONT lacks power due to that power failure.
To this end, battery backup has also been provided within the ONT and within the environment for the ONT, and for customer telephone instruments connected to that ONT. But, in contrast with the central office location of POTS battery backup, ONT battery backup is located proximate its associated ONT. This ONT battery backup unit (BBU) can be designed to include certain customer—useful features. One such feature is an audio alarm which sounds when the backup battery voltage level is low. For example, application Ser. No. 11/460,499, filed Jul. 27, 2006, entitled: “Optical Network Terminal Power Failure Management” relates to managing a low ONT battery voltage audio alarm; this application is assigned to the assignee of the instant application and is incorporated herein by reference in its entirety.
However, a sounding-alarm, if battery voltage is low due to utility company power failure, or for other reasons, is not always heard by the customer in sufficient time for the customer to take appropriate action, particularly if the ONT is installed in a relatively remote place on the customer's premises, such as outside of the house or in the basement. Under certain conditions, such an alarm can be sounded for several hours and never be heard by occupants of the customer's premises. The backup battery can be discharged completely during that critical time period. If the backup battery is completely discharged and, on the one hand, if that battery discharge was due to a utility company power failure, then communication services via the ONT would be completely unavailable unless and until power is restored by the power company. On the other hand, if battery discharge was due to other reasons, the battery is then useless if needed for backup purposes if and when there is a utility company power failure.
In connection with this battery discharge problem, there is a need to obtain and maintain data on the state of the battery in an ongoing manner. It would be useful to know how the voltage level of a battery is trending over a period of time to enable predictions about future failure of that battery. It would be even more useful if this information could be obtained and maintained on each one of a large number of batteries deployed, respectively, at a like number customer premises, where such data obtained over a large population of batteries can offer valuable and on-going statistical insight to battery performance and failure as a function of many variables such as, e.g., battery manufacturer, battery model, battery chemistry, and battery placement (internal/external) at the customer premises.